February 1 2016
According to the Cuban magazine Bohemia, the epidemic of dengue hemorrhagic fever that occurred in Cuba in 1981 was deliberately introduced in the country by the United States.
The bio-attack triggered an epidemic that affected 344,203 citizens, killing 158 including 101 children, and costing the government 103.2 million dollars.
The publication noted on its website that the article “First Epidemic of Dengue Hemorrhagic Fever in the Americas, 1981” offers new knowledge about the causal agent and scientific evidence that corroborate the accusation made by Cuba.
Studies carried out to characterize the causative strain of the 1981 DHF epidemic
Its main author, Doctor in Sciences Rosmari Rodríguez, researcher at the Pedro Kouri Tropical Medicine Institute (IPK), was awarded the Grand Award in the annual public health contest in 2015.
Rodriguez noted that in the 1990s, IPK, along with similar institutions from other countries, carried out studies to characterize the causative strain of the 1981 DHF epidemic.
These investigations allowed them to obtain the sequence of about 300 basic data pairs, of the almost 11,000 having the complete viral genome, with the use of methodologies for manual sequencing and the very simple tools available then for bioinformatics.
The laboratory New Guinea C, isolated in 1944
This was sufficient to demonstrate that the causative strain of the epidemic in 1981 had great similarity with the laboratory New Guinea C, isolated in 1944, the first time that dengue fever was isolated in the world, she explained.
Cuban scientists sequenced the complete genome of viral strains collected at different stages of the epidemic, to demonstrate that it was not a laboratory contamination.
In 1983, Cuba denounced this biological aggression
In 1983, Bohemia reminds, scientist Gustavo Kourí denounced this biological aggression against Cuba during a Congress of Tropical Medicine in Calgary, Canada.
The Cubans showed evidence in 1995 about the similarity of the circulating strain in 1981 in Cuba, with the first of dengue 2 isolated in the world, known as reference or prototype.
The IPK acquired in 2008 modern automatic sequencing technology, to return to the strains of 1981, preserved for more than 30 years in a refrigerator at 80, and made the entire process for the first time in Cuba.
Cuban researchers were able to amplify and sequence the full genome of the original strains obtained in different moments of the epidemic in 1981, using bioinformatic tools that allowed you to define with high certainty the genetic relatedness of the 81 Cuban strains with New Guinea C.
Simultaneous outbreaks in different locations in Cuba
After analyzing the sequences of strains of different moments of the epidemic they noticed that, even though all were similar in New Guinea in 1944, there were differences between Cuban strains. That is, that the virus underwent changes during the epidemic period.
That fact rejects the hypothesis of contamination of laboratory, as if it were that, all strains tested should have the same sequence.
Also, it supports the fact that the epidemic broke out at three points in the country at the same time the Cuban complaint: Eastern, Central, and West.
Dengue outbreaks are detected usually from an index case in a given area, around which new patients appear. Then they expand to other territories with the movement of infected persons, and a gradual increase of patients reaching epidemic peaks, which largely depend on the density of mosquitoes observed.